CrbS/R homologs control expression of <i>acsA</i> in <i>Pseudomonas aeruginosa</i>.

<p>Quantitative real-time PCR was used to measure <i>acsA</i> transcript abundance in an <i>mxtR</i> sensor kinase mutant (A), <i>erdR</i> response regulator mutant (B), and REC domain mutants of either <i>mxtR</i> (C) or <i>erdR</i> (D) in <i>Pseudomonas aeruginosa</i>. <i>acsA</i> transcript levels were measured relative to the <i>clpX</i> housekeeping protease transcript levels. Strains were transformed with either an empty vector plasmid pPSV38, or a pPSV38-<i>erdR</i> (pErdR) expression vector, as indicated. Statistical significance was determined by comparing results of each mutant strain to the wild-type strain. (*) denotes a P-value less than 0.05, (**) denotes a P-value less than 0.01, and (***) denotes a P-value less than 0.001.